Subjects

The CAP Theorem

Understand why distributed systems can only guarantee two of Consistency, Availability, and Partition Tolerance — and how real-world databases (Cassandra, Zookeeper, DynamoDB, Postgres) navigate this fundamental constraint.

Database Indexing

Learn how B-tree and hash indexes work internally, how the query planner uses them, when to create composite and covering indexes, and how to diagnose slow queries using EXPLAIN ANALYZE.